Medical instrumentaria of the kind described hereinabove are known in many ways. In particular femur cavities into which a hip joint stem of a hip joint endoprosthesis is to be inserted are prepared with rasp instruments comprised by such medical instrumentaria. A surgeon begins in the preparation of the femur cavity with the smallest available rasp shank and drives this into the femur cavity. Then, the rasp shank is again removed from the femur cavity and a somewhat larger rasp shank is driven in. This procedure is repeated until the proper size of the rasp shank is determined.
Numerous surgeons use the largest rasp shank driven in to test rotational stability thereof in the femur. This is supposed to simulate rotational stability for example of a hip joint stem to ultimately be implanted.
A rasp shank with a toothing that is formed by the rasp teeth described at the outset which are formed circumferential or at least partially circumferential on the side faces of the rasp shank has been shown in tests to be not particularly well suited with respect to determine the rotational stability.
It is therefore the object of the present invention to improve a handling of a medical instrumentarium of the kind described at the outset, in particular in the preparation of a bone cavity, in particular a femur cavity.